Perspective machine

ABSTRACT

This invention relates to a perspective machine which is used by draftsmen and the like and will enable the draftsmen to provide a vanishing point which is either on the drafting table or beyond the limits of that table. The straight edge of the machine can be so adjusted that the lines drawn by the draftsman are either exactly horizontal, exactly vertical or most angle there between.

nited States Patent Tennant Mar. 25, 1975 PERSPECTIVE MACHINE [76] Inventor: Wayne W. Tennant, 121 Wutzke 'm Aegerter Ave" Garden Grove Calif Assistant E.\'ammer.lohn W. Shepperd [22] F1 d D 10 1973 Attorney, Agent, or Firm-William C. Babcock re ec.

[2i] Appl. No.1 423,233 ABSTRACT 52 us. Cl. 33/77 This invention relates to Perspective machine which 511 1m. (:1 B43] 13/14 is used by draftsmen and like and will enable the 58 Field of Search 33/77 draftsmen Provide a vanishing POint which is either on the drafting table or beyond the limits of that table. [56] References Cited The straight edge of the machine can be so adjusted UNITED STATES PATENTS that the lines drawn by the draftsman are either exactly horizontal, exactly vertical or most angle there 3,191,307 I 6/1965 DeAngelis 33/77 between- FOREIGN PATENTS OR APPLICATIONS Italy 33/77 4 Claims, 4 Drawing Figures PERSPECTIVE MACHINE An object of my invention is to provide a novel perspective machine which can. be readily and easily adjusted by the draftsman to enable him to produce lines which will intersect either within the limits of the drafting table or outside of those limits.

Still another object is to provide a novel drafting machine which can be readily mounted on a drafting table and is simple to use and effective in operation.

Other objects and advantages of my invention may appear from the accompanying drawings, the subjoined detailed description and the appended claims.

In the drawing:

FIG. 1 is a side elevation of'my perspective machine.

FIG. 2 is a top plan view of the same.

FIG. 3 is a plan view of the perspective machine illustrating one position of the parts.

FIG. 4 is a plan view of the perspective machine with the parts in another position than that shown in FIG. 3.

Referring more particularly to the drawing: The numeral 1 indicates the top ofa drafting table of the usual and well-known type. My perspective machine is mounted on top of the drafting table in the following manner: A C-clamp 2 is fixedly attached to one edge of the table 1 by means of the set screw 3. The top plate 4 of the clamp rests on top of the table 1 and is substantially parallel to one edge of the table.

My perspective machine consists of a straight edge 5 which is formed with a head 6 at one end thereof. This head is preferrably integral with the straight edge 5 and lies substantially in the same horizontal plane. A pair of arms 7 and 8 are pivotly attached to one end of the head 6- by the pins 9 and 10 respectively. The ends of the arms 7 and 8 opposite the pivots 9 and 10 are pivotly attached tothe top plate 4 by the pins 11 and 12 respectively. It will be noted that the length of the arms 7 and 8 are exactly equal between the pins 11-9 and 12-10. The pins 11 and 12 are slidably mounted in the slot 13 which is formed in the plate 4. Thus, the arms 7 and 8 can be adjusted to be parallel as shown in FIG. 3 or at an angle to each other as in FIG. 4. This adjustment is accomplished in the following manner: A threaded spindle 14 is threaded through the arm extension 15 of the arms 8 and also the extention 16 of the arm 7. Thus, by rotating the knurled nut 17, the spindle can be rotated to adjust the pins 11 or 12 relative to each other and also to either place the arm 7 and 8 in parallel relation or at an angle to each other as shown in FIG. 4. Thus the blade 5 can be placed either in a horizontal plane or at an angle to the horizontal depending on the requirements of the vanishing point, wherever this might lie.

Having described my invention, I claim:

1. A perspective machine comprising a straight edge, a pair of spaced arms means pivotaly securing one end of said arms to the straight edge, a clamp, having a slot therein, means pivotally securing each of said arms to the clamp, said means pivotally securing said arms to the clamp extending through the slot, and adjustable means extending through each of said arms to move said arms relative to each other.

2. A perspective machine as recited in claim 1 and said adjustable means including a threaded spindle screwed into each of said arms.

3. A perspective machine as recited in claim 1 and the distance from the pivotal mounting of each of the arms to the straight edge and the pivotal mounting of the arms to the clamp being equal.

4. A perspective machine as recited in claim 1 and said adjustable means including a threaded spindle screwed into each of said arms and the distance from the pivotal mounting of each of the arms to the straight edge and the pivotal mounting of the arms to the clamp, being equal. 

1. A perspective machine comprising a straight edge, a pair of spaced arms means pivotaly securing one end of said arms to the straight edge, a clamp, having a slot therein, means pivotally securing each of said arms to the clamp, said means pivotally securing said arms to the clamp extending through the slot, and adjustable means extending through each of said arms to move said arms relative to each other.
 2. A perspective machine as recited in claim 1 and said adjustable means including a threaded sPindle screwed into each of said arms.
 3. A perspective machine as recited in claim 1 and the distance from the pivotal mounting of each of the arms to the straight edge and the pivotal mounting of the arms to the clamp being equal.
 4. A perspective machine as recited in claim 1 and said adjustable means including a threaded spindle screwed into each of said arms and the distance from the pivotal mounting of each of the arms to the straight edge and the pivotal mounting of the arms to the clamp, being equal. 